Research On Medium Voltage Distribution Networks Line Loss Core Index System And Line Loss Model With Characteristics Of Fuzzy Clustering

Line loss is an indicator that shows the energy consumed during transmission, it can direct response technology and management level of the grid. And line loss is one of the key assessment indicators of the grid company. As a platform for energy distribution, the grid company should also pay more attention to reduce their own energy consumption, especially on line loss. Compared with the transmission network, the medium voltage distribution network(MVDN) has the following characteristics: the voltage level is low, the network topology is not clear, the number of monitoring equipment is small, the line loss rate is relatively high. In China, the medium and low voltage distribution network line loss account for 60% of the entire line loss, and 10 kV MVDN takes the highest proportion. So the MVDN line loss should be further studied.In this paper, 10 kV distribution feeders are researched. The feeders have the characteristics of wide coverage and multi-type of end-users, which results in the significant differences between line properties and operating parameters of the feeders. Traditional line loss rate calculation methods don’t consider the differences above. Their results can’t reflect the overall level of the MVDN line loss, so they are not conducive for the line loss refinement and difference management to carry and promote. Therefore, in this paper, the differences and relationships between line properties, operating parameters are fully taken into account. And the indicators are analyzed in depth based on an extensive collection of indicators. The indicators are used to establish MVDN line loss core-indicator system, which is used to cluster the sample feeders and determine the ground-state-feeders. Then the line loss model with characteristics of fuzzy clustering is designed. In this model, equivalent resistance method is used to calculate the line loss of ground-state-feeders, which is regarded as the line loss base value of the type of feeders. At last, the sensitivity method is used to calculate the line loss of non-ground-state-feeders, and the benchmarking values of each type are determined. This line loss model can achieve a variety of applications, including line loss rolling calculation and loss reduction potentiality calculation.When the feeder types and line loss value are determined, the line loss management indicators can be issued reasonably. The results will provide data support for the line loss management work, and promote energy conservation and emission reduction work.